The Multidisciplinary Training Program in Environmental Toxicology (MTPET) described in this application produces scientists having a base knowledge in environmental toxicology coupled with research expertise gained in a departmentally-based, biomedical science graduate program. Predoctoral trainees must meet the full Ph.D. requirements of their "home" department and complete the coursework, research and interactive aspects of the MTPET administered through the Institute for Environmental Toxicology (lET). The degree awarded recognizes the dual nature of the training by listing the department-environmental toxicology (e.g., Ph.D. in "Biochemistry and Molecular Biology- Environmental Toxicology"). Graduates of the program are well equipped to conduct research and interact with other scientists in the course of solving complex environmental toxicological problems that require collaborative, multidisciplinary approaches. Fifteen training faculty conduct predoctoral training in five departmental Ph. D. programs (Pharmacology and Toxicology, Biochemistry and Molecular Biology, Food Science and Human Nutrition, Zoology, Cell and Molecular Biology). Added to the department-based education and environmental toxicology research training in participating departments are didactic, toxicology-oriented courses and other requirements of the MTPET. This coursework and less formal multidisciplinary interactions and activities provided by the lET and MTPET impart a wider scope of knowledge than is available within individual departmental programs. Research topics for trainees are available in mechanisms-related toxicology encompassing various organ systems (e.g., hepatic, immune, endocrine, neuronal, respiratory), carcinogenesis, and food safety. There is an integrative biology emphasis to the research training, which encompasses whole animal, cell-based, molecular and genomic methodologies to understand mechanisms of toxicity and factors governing susceptibility. Postdoctoral trainees conduct research in the laboratory of one (or more) of the training faculty and gain additional environmental toxicology experience through participation in lET and MTPET activities and courses. This application is for support of six predoctoral and three postdoctoral trainees, thereby continuing a highly effective multidisciplinary training program which mixes formal and informal approaches to prepare graduates to make significant contributions to the field of environmental toxicology.